okay so i had unprotected sex doing my period on sept 5. and two days later my period ended early and my period was suppose to start again around the 24th but i bleeding a little mostly brown & pinkish, sometimes redish but not heavy, i only see it when i whip, i took a pregnancy test today and it was negative. does this mean i can be pregnant ? i just took the test early? because i been having pregnancy symptoms! what should i do?